Synthetic Bone Substitute Engineered with Amniotic Epithelial Cells Enhances Bone Regeneration after Maxillary Sinus Augmentation

Abstract

BackgroundEvidence has been provided that a cell-based therapy combined with the use of bioactive materials may significantly improve bone regeneration prior to dental implant, although the identification of an ideal source of progenitor/stem cells remains to be determined.AimIn the present research, the bone regenerative property of an emerging source of progenitor cells, the amniotic epithelial cells (AEC), loaded on a calcium-phosphate synthetic bone substitute, made by direct rapid prototyping (rPT) technique, was evaluated in an animal study.Material And MethodsTwo blocks of synthetic bone substitute (∼0.14 cm3), alone or engineered with 1×106 ovine AEC (oAEC), were grafted bilaterally into maxillary sinuses of six adult sheep, an animal model chosen for its high translational value in dentistry. The sheep were then randomly divided into two groups and sacrificed at 45 and 90 days post implantation (p.i.). Tissue regeneration was evaluated in the sinus explants by micro-computer tomography (micro-CT), morphological, morphometric and biochemical analyses.Results And ConclusionsThe obtained data suggest that scaffold integration and bone deposition are positively influenced by allotransplantated oAEC. Sinus explants derived from sheep grafted with oAEC engineered scaffolds displayed a reduced fibrotic reaction, a limited inflammatory response and an accelerated process of angiogenesis. In addition, the presence of oAEC significantly stimulated osteogenesis either by enhancing bone deposition or making more extent the foci of bone nucleation. Besides the modulatory role played by oAEC in the crucial events successfully guiding tissue regeneration (angiogenesis, vascular endothelial growth factor expression and inflammation), data provided herein show that oAEC were also able to directly participate in the process of bone deposition, as suggested by the presence of oAEC entrapped within the newly deposited osteoid matrix and by their ability to switch-on the expression of a specific bone-related protein (osteocalcin, OCN) when transplanted into host tissues.

Gestational stage affects amniotic epithelial cells phenotype, methylation status, immunomodulatory and stemness properties

“…In fact, while osteogenic cell evolution appeared to be easily obtained by incubating oAECs isolated from mid [3, 21] to term gestation amnia, oAECs collected from early gestation amnia have proved to be highly refractory to the osteogenic-inductive cultural condition.…”

“…The differentiation was assessed by Oil Red O and RT-PCR for a previously identified [21] adipogenic-specific marker, the lipoprotein lipase ( LPL ).…”

3D Printing of Calcium Phosphate Ceramics for Bone Tissue Engineering and Drug Delivery

“…For example, Barboni et al (2013) demonstrated the osteogenic potential of ovine amniotic epithelial cells (oAEC) seeded on a CaP scaffold fabricated by material extrusion of a paste-like aqueous ceramic slurry of HA/ β -TCP. 4 When implanted in sheep to augment maxillary sinus defects, oAEC-seeding of the 3D printed CaP scaffolds significantly increased bone ingrowth into the defect and accelerated angiogenesis when compared to scaffolds without cells.…”

“…A wide variety of cells have been used for such characterization, including osteoblasts, 7,14,20,24,71,91 preosteoblastic cells, 19,49 stromal cells, 22,71,98 osteoclasts, 21 mesenchymal stem cells (MSCs), 68,72 epithelial cells, 4 and Schwan cells. 80 Cell viability, 14,21,22,24,71,80,98 proliferation, 14,19,21,22,24,32,40,68,71,72,80,91 and cytotoxicity 19,91 assays all show a general consensus of favorable biocompatibility regardless of the 3D printing method using different biomaterials.…”

Amniotic Epithelial Cells: A New Tool to Combat Aging and Age-Related Diseases?

“…Other therapeutic applications of AECs in laboratory animals include support of the regenerative process in tendon defects (Barboni et al, 2012a,b) via collagen type I production (Muttini et al, 2013), improvement in bone regeneration in vivo through implantation of scaffold-loaded AECs (Barboni et al, 2013), and reduction in the early host immune response to the scaffold (Jiawen et al, 2014). …”